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Log10(LR)

Definition

The base-10 logarithm of the likelihood ratio, sometimes called the weight of evidence (following I.J. Good). A log10(LR) of 1 corresponds to LR = 10, log10(LR) of 2 to LR = 100, and log10(LR) of 3 to LR = 1000. Logarithmic representation is used in verbal scales because LR values span many orders of magnitude.

Related terms

ENFSI guideline
The European Network of Forensic Science Institutes Guideline for Evaluative Reporting in Forensic Science (2015, updated 2016). It defines the propositions framework,...
Jeffreys scale
A logarithmic scale for Bayes factors proposed by Harold Jeffreys in Theory of Probability (1961). Levels run from 'barely worth mentioning' at...
Likelihood ratio (LR)
The ratio of two conditional probabilities: the probability of the observed evidence given the prosecution's hypothesis (same source), divided by the probability...
Transposition fallacy
The error of treating the probability of the evidence given a hypothesis as though it were the probability of the hypothesis given...
Verbal equivalence scale
A table that assigns a verbal phrase to a range of LR values or log10(LR) values. The phrase is used in written...

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